The 49ers filled the spot on the 53-man roster Tuesday with the signing of fullback Owen Marecic to replace Williams, who was placed on season-ending injured reserve. Demarcus Dobbs and Tony Jerod-Eddie remain as the only backup defensive linemen behind starters Justin Smith, Ray McDonald and Glenn Dorsey, who takes over at nose tackle.

Dial is just one player the 49ers expect to get later in the season who can help the 49ers over the final months of the regular season:

DT Quinton Dial: The 49ers have a high opinion of Dial, whom they selected in the fifth round from Alabama. He underwent surgery in January to repair torn cartilage and ligament damage in his toe. The 49ers have been ultra-cautious when it comes to his rehabilitation, so he should be ready to practice shortly after he becomes eligible.

Under rules governing non-football injury and physically unable to perform, clubs are allowed to begin practicing those players beginning after the sixth week (Oct. 15) through the conclusion of the 11th weekend of games (Nov. 18). At any time over a 21-day period after a player begins practicing, the team can activate the player to the 53-man roster.

Dial (6 foot 5, 318 pounds) is envisioned as a base nose tackle in the 49ers’ defense. He could be the team’s primary backup to starter Glenn Dorsey over the second half of the season.

DT Tank Carradine: How much do the 49ers like Carradine? He was the second player they chose in this draft, despite knowing he was coming off a torn ACL that cut short his final season at Florida State.

Prior to the draft, many NFL teams believed there were some shortcuts taken in Carradine’s rehabilitation to get him ready quickly. It appears as if the 49ers restarted Carradine’s rehabilitation after selecting him in the second round – similar to what they’ve done with running back Marcus Lattimore (more on him later).

Carradine continues to rehab daily at the 49ers’ practice facility. He should be available to being practicing shortly after Week 6, too. The 49ers have no plan to rush him onto the field, but he can be a contributor down the stretch with his ability to play anywhere on the defensive line (except nose tackle) in base or nickel.

WR Mario Manningham: He is also rehabbing daily under the 49ers’ direction. He sustained his left knee injury (torn ACL and posterior cruciate ligament) on Dec. 23 in Seattle. He should be available shortly after the sixth week, and could immediately step in as one of the team's top two wide receivers.

CB Eric Wright: He is at the 49ers’ practice facility every day, working behind the scenes after reporting to the 49ers just prior to the start of the regular season to take care of some personal issues. He signed a one-year contract with the 49ers on Aug. 8. Always considered a physically talented player, Wright has a chance to become an immediate contributor after returning from the non-football illness list after Week 6.

WR Michael Crabtree: He is still appears to be on pace for a late-season return from a torn right Achilles tendon he sustained on May 21. With a six-month recovery, it’s conceivable he could be available at the beginning of December. But how long will it take him to get into football shape?

RB Marcus Lattimore: The 49ers have no intention of playing Lattimore (shown, below right) this season. They want to make sure the former South Carolina star is fully recovered from the grisly right leg injury that consisted a dislocated knee and three torn ligaments he sustained last October. The 49ers believe Lattimore can eventually take over for Frank Gore as the featured back, so they want him ready for 2014 and beyond.

LB Nick Moody: Like the above players, he does not count against the 49ers’ 53-man roster because he was placed last week on injured reserve/designated for return. Moody, one of the team’s core special teams players, sustained a broken right hand in the season opener. The rookie is expected to miss six more games before he is eligible to return to action for the final eight games of the regular season.